U.S. patent application number 13/394611 was filed with the patent office on 2012-07-05 for vehicle seat.
Invention is credited to Manabu Ishimoto, Keisuke Ishizaki.
Application Number | 20120168596 13/394611 |
Document ID | / |
Family ID | 43732120 |
Filed Date | 2012-07-05 |
United States Patent
Application |
20120168596 |
Kind Code |
A1 |
Ishimoto; Manabu ; et
al. |
July 5, 2012 |
VEHICLE SEAT
Abstract
A vehicle seat configured in such a manner that vibration
occurring in the seat body can be suppressed without adding a
special device such as a dynamic damper. A vehicle seat is
configured in such a manner that an upper rail (26) connected to
the seat body is slidably supported by a lower rail (28), which is
affixed to the vehicle body side, through a pair of slide guides
(42, 44) disposed next to each other in the front-rear direction of
the seat. The distance (L) between the slide guides (42, 44) is set
to be less than the half of the maximum slide amount (S) of the
upper rail (26) relative to the lower rail (28). As a result of the
configuration, the rigidity of support of the seat body by the
vehicle body is reduced to reduce the resonance frequency of the
seat body in the front-rear direction. This enables the resonance
frequency of the seat body in the front-rear direction to be
shifted from the resonance frequency of the vehicle body when the
engine of the vehicle is idling.
Inventors: |
Ishimoto; Manabu;
(Chiryu-shi, JP) ; Ishizaki; Keisuke; (Nishio-shi,
JP) |
Family ID: |
43732120 |
Appl. No.: |
13/394611 |
Filed: |
September 10, 2009 |
PCT Filed: |
September 10, 2009 |
PCT NO: |
PCT/JP2009/065874 |
371 Date: |
March 7, 2012 |
Current U.S.
Class: |
248/430 |
Current CPC
Class: |
B60N 2/0722 20130101;
B60N 2/0727 20130101; B60N 2/0715 20130101; B60N 2/071 20130101;
B60N 2/073 20130101; B60N 2/0725 20130101 |
Class at
Publication: |
248/430 |
International
Class: |
B60N 2/07 20060101
B60N002/07 |
Claims
1. A vehicle seat supported such that an upper rail connected to a
seat body is capable of sliding in a seat front-rear direction
relative to a lower rail fixed at the vehicle body side through a
pair of slide guides disposed in a row along the seat front-rear
direction, wherein: the separation between the seat front-rear
direction central portion of a first of the slide guides and the
seat front-rear direction central portion of the second of the
slide guides is narrower than half the maximum slide amount of the
upper rail with respect to the lower rail; at least one of the
upper rail and/or the lower rail comprises projection portion(s)
projecting out towards the opposing rail side in the vehicle
up-down direction at the front end portion or the rear end portion
or both the front and rear end portions; a gap is provided between
the leading end of the projection portion(s) and the opposing rail
such that the gap has a smaller up-down direction dimension than
the up-down direction dimension of the projection portion(s); and
the leading end of the projection portion(s) suppress bowing by
making contact with the opposing rail when the upper rail bows
towards the lower rail side due to load applied from the seat body
side, and wherein: the upper rail comprises a front upper
projection portion and a rear upper projection portion disposed
further to the seat rear side than the front upper projection
portion; the lower rail comprises a front lower projection portion
and a rear lower projection portion disposed further to the seat
rear side than the front lower projection portion; each of the pair
of slide guides comprises a guide body and a ball rotatably
attached to the guide body; the upper rail is restricted from
sliding towards the seat front side with respect to the lower rail
by the guide body of the first slide guide, which is disposed at
the center between the rear upper projection portion and the front
lower projection portion in a state in which the upper rail is
disposed at the center of its sliding range with respect to the
lower rail, being sandwiched between the rear upper projection
portion and the front lower projection portion; the upper rail is
restricted from sliding towards the seat rear side with respect to
the lower rail by the guide body of the second slide guide, which
is disposed at the center between the front upper projection
portion and the rear lower projection portion in a state in which
the upper rail is disposed at the center of the sliding range with
respect to the lower rail, being sandwiched between the front upper
projection portion and the rear lower projection portion, and the
projection portion(s) are structured by at least one of the front
lower projection portion or the rear lower projection portion.
2. (canceled)
3. The vehicle seat of claim 1, wherein: a first side contact
portion that makes contact with the rear upper projection portion
and the front lower projection portion is provided to the guide
body of the first slide guide, and a second side contact portion
that makes contact with the front upper projection portion and the
rear lower projection portion is provided to the guide body of the
second slide guide; the rear upper projection portion, the front
lower projection portion and the first side contact portion are
disposed further to a first side in the seat left-right direction
than seat left-right direction central portions of the upper rail
and the lower rail; and the front upper projection portion, the
rear lower projection portion and the second side contact portion
are disposed further to the second side in the seat left-right
direction than seat left-right direction central portions of the
upper rail and the lower rail.
4. The vehicle seat of claim 1 wherein: the front lower projection
portion is provided to a front end portion of the lower rail, the
rear lower projection portion is provided to a rear end portion of
the lower rail, and the upper rail is restricted from sliding
towards the seat front side with respect to the lower rail by the
guide body of the slide guide at the seat front side being
sandwiched between the rear upper projection portion and the front
lower projection portion; and the upper rail is restricted from
sliding towards the seat rear side with respect to the lower rail
by the guide body of the slide guide on the seat rear side being
sandwiched between the front upper projection portion and the rear
lower projection portion.
5. (canceled)
6. The vehicle seat of claim 1, wherein: the lower rail comprises a
top wall whose bottom face faces towards the top face of the upper
rail and a bottom wall whose top face faces towards the bottom face
of the upper rail; the projection portion(s) are provided to at
least one of the top face side of the front end portion of the
upper rail and/or the bottom face side of the front end portion of
the top wall; and the projection portion(s) are provided to at
least one of the bottom face side of the rear end portion of the
upper rail and/or the top face side of the rear end portion of the
bottom wall.
7. The vehicle seat of claim 1, wherein: the lower rail comprises a
top wall whose bottom face faces towards the top face of the upper
rail and a bottom wall whose top face faces towards the bottom face
of the upper rail; the projection portion(s) are provided to at
least one of the bottom face side of the front end portion of the
upper rail and/or the top face side of the front end portion of the
bottom wall; and the projection portion(s) are provided to at least
one of the top face side of the rear end portion of the upper rail
and/or the bottom face side of the rear end portion of the top
wall.
8. The vehicle seat of claim 1, wherein: the seat left-right
direction end sides of the bottom face of the upper rail are
disposed closer to the lower rail than the seat left-right
direction central portion of the bottom face of the upper rail; and
the projection portion(s) are provided between the seat left-right
direction end sides of the bottom face of the upper rail and the
lower rail.
9. The vehicle seat of claim 1, wherein: the lower rail comprises a
rail body and bracket(s) for connecting the seat front-rear
direction end portions of the rail body to the vehicle body; and
the projection portion(s) are provided to the bracket(s).
10. The vehicle seat of claim 1, wherein the projection portion
projects from the upper rail in the vicinity of below a connection
portion to the seat body towards the lower rail side.
11. The vehicle seat of claim 1, wherein a bent portion is provided
to the projection portion.
12. The vehicle seat of claim 11, wherein a gap is provided between
at least one of the upper rail and the lower rail and the leading
end of the projection portion(s).
Description
TECHNICAL FIELD
[0001] The present invention relates to a vehicle seat in which an
upper rail connected to a seat body supported so as to be capable
of sliding with respect to a lower rail fixed to the vehicle body
side through a pair of slide guides.
BACKGROUND ART
[0002] Related technology is known for suppressing vibration from
occurring in a vehicle seat, using a technique of fixing a dynamic
damper to the vehicle seat (see for example Japanese Patent
Application Laid-Open (JP-A) No. 2006-298353).
DISCLOSURE OF INVENTION
Technical Problem
[0003] However, due to such a dynamic damper being both large and
complicated, problems arise such as the difficulty in securing a
mounting base for attaching to the vehicle seat, and increased
manufacturing cost and weight of the vehicle seat.
[0004] In consideration of the above circumstances, an object of
the present invention is a vehicle seat capable of suppressing
vibration from occurring in a seat body without adding an separate
device such as a dynamic damper.
Solution to Problem
[0005] A first aspect of the present invention provides a vehicle
seat supported such that an upper rail connected to a seat body is
capable of sliding in a seat front-rear direction relative to a
lower rail fixed at the vehicle body side through a pair of slide
guides disposed in a row along the seat front-rear direction,
wherein the separation between the seat front-rear direction
central portion of a first of the slide guides and the seat
front-rear direction central portion of the second of the slide
guides is narrower than half the maximum slide amount of the upper
rail with respect to the lower rail.
[0006] In the vehicle seat of the first aspect the separation
between the front and rear pair of the slide guides is made as
narrow as a specific value or narrower. The supporting rigidity of
the seat body with respect to the vehicle body is accordingly
lowered, lowering the seat body front-rear direction resonance
frequency. The seat body front-rear direction resonance frequency
can accordingly be shifted from a resonance frequency of the
vehicle body, such as the resonance frequency of the vehicle during
engine idling. Vibration of the seat body can hence be suppressed
from occurring without providing an additional separate device such
as a dynamic damper.
[0007] A vehicle seat of a second aspect of the present invention
is the vehicle seat of the first aspect wherein: the upper rail
includes a front upper projection portion and a rear upper
projection portion disposed further to the seat rear side than the
front upper projection portion; the lower rail includes a front
lower projection portion and a rear lower projection portion
disposed further to the seat rear side than the front lower
projection portion; the first slide guide, which is disposed at the
center between the rear upper projection portion and the front
upper projection portion in a state in which the upper rail is
disposed at the center of its sliding range with respect to the
lower rail, restricts the upper rail from sliding towards the seat
front side with respect to the lower rail by the first slide guide
being sandwiched between the rear upper projection portion and the
front lower projection portion; and the second slide guide, which
is disposed at the center between the front upper projection
portion and the rear lower projection portion in a state in which
the upper rail is disposed at the center of the sliding range with
respect to the lower rail, restricts the upper rail from sliding
towards the seat rear side with respect to the lower rail by the
second slide guide being sandwiched between the front upper
projection portion and the rear lower projection portion.
[0008] In the vehicle seat of the second aspect, when the upper
rail slides with respect to the lower rail towards the seat front
side, the first slide guide is sandwiched between the rear upper
projection portion provided to the upper rail and the front lower
projection portion provided to the lower rail. The upper rail is
thereby restricted from sliding with respect to the lower rail
towards the seat front side.
[0009] The rear upper projection portion of the upper rail here is
disposed further towards the seat rear side than the front upper
projection portion of the upper rail, and the front lower
projection portion of the lower rail is disposed further towards
the seat front side than the rear lower projection portion of the
lower rail. The separation distance between the rear upper
projection portion and the front lower projection portion can
accordingly be set large in the state in which the upper rail is
disposed at the center of its sliding range with respect to the
lower rail. A large siding amount can accordingly be set for the
upper rail from the central disposed state referred to above
towards the seat front side (the siding amount of the upper rail
until the first slide guide is sandwiched between the rear upper
projection portion and the front lower projection portion).
[0010] When the upper rail slides with respect to the lower rail
towards the seat rear side, the second slide guide is sandwiched
between the front upper projection portion provided to the upper
rail and the rear lower projection portion provided to the lower
rail. The upper rail is accordingly restricted from sliding with
respect to the lower rail towards the seat rear side.
[0011] The front upper projection portion of the upper rail is
disposed here further towards the seat front side than the rear
upper projection portion of the upper rail, and the rear lower
projection portion of the lower rail is disposed further to the
seat rear side than the front lower projection portion of the lower
rail. The separation distance between the front upper projection
portion and the rear lower projection portion can accordingly be
set large in the state in which the upper rail is disposed at the
center of its sliding range with respect to the lower rail. A large
siding amount can accordingly be set for the upper rail from the
central disposed state referred to above towards the seat rear side
(the siding amount of the upper rail until the second slide guide
is sandwiched between the front upper projection portion and the
rear lower projection portion).
[0012] Consequently, in the vehicle seat the maximum siding amount
of the upper rail with respect to the lower rail can be set larger
than the overall length of the upper rail and the lower rail.
[0013] A vehicle seat of a third aspect of the present invention is
the vehicle seat of the second aspect wherein: a first side contact
portion that makes contact with the rear upper projection portion
and the front lower projection portion is provided to the first
slide guide, and a second side contact portion that makes contact
with the front upper projection portion and the rear lower
projection portion is provided to the second slide guide; the rear
upper projection portion, the front lower projection portion and
the first side contact portion are disposed further to a first side
in the seat left-right direction than seat left-right direction
central portions of the upper rail and the lower rail; and the
front upper projection portion, the rear lower projection portion
and the second side contact portion are disposed further to the
second side in the seat left-right direction than seat left-right
direction central portions of the upper rail and the lower
rail.
[0014] In the vehicle seat of the third aspect, when the upper rail
slides towards the seat rear side with respect to the lower rail,
the first side contact portion provided to the first slide guide
makes contact with the rear upper projection portion of the upper
rail and the front lower projection portion of the lower rail. The
first slide guide is accordingly sandwiched between the rear upper
projection portion and the front lower projection portion. When the
upper rail slides with respect to the lower rail towards the seat
rear side, the second side contact portion provided to the second
slide guide makes contact with the front upper projection portion
of the upper rail and the rear lower projection portion of the
lower rail. The second slide guide is accordingly sandwiched
between the front upper projection portion and the rear lower
projection portion.
[0015] In such a vehicle seat, the rear upper projection portion,
the front lower projection portion, and the first side contact
portion are disposed further to a first side in the seat left-right
direction than seat left-right direction central portions of the
upper rail and the lower rail. The front upper projection portion,
the rear lower projection portion and the second side contact
portion are disposed further to the second side in the seat
left-right direction than seat left-right direction central
portions of the upper rail and the lower rail. Accordingly, a
simple structure is achieved that enables unwanted interference of
the rear upper projection portion with respect to the rear lower
projection portion and the second side contact portion, and
unwanted interference of the front upper projection portion with
the front lower projection portion and the first side contact
portion to be avoided.
[0016] A vehicle seat of a fourth aspect of the present invention
is the vehicle seat of the second aspect or the third aspect
wherein: the front lower projection portion is provided to a front
end portion of the lower rail, the rear lower projection portion is
provided to a rear end portion of the lower rail, and the upper
rail is restricted from sliding towards the seat front side with
respect to the lower rail by the slide guide at the seat front side
being sandwiched between the rear upper projection portion and the
front lower projection portion; and the upper rail is restricted
from sliding towards the seat rear side with respect to the lower
rail by the slide guide on the seat rear side being sandwiched
between the front upper projection portion and the rear lower
projection portion.
[0017] In the vehicle seat of the fourth aspect, the front lower
projection portion is provided to the front end portion of the
lower rail, and the rear lower projection portion is provided to
the rear end portion of the lower rail. Accordingly, the front
lower projection portion and the rear lower projection portion can
be configured as a common component as a detachment prevention
stopper for preventing detachment of the slide guides from the
front-rear direction end portions of the lower rail.
[0018] A vehicle seat of a fifth aspect of the present invention is
the vehicle seat of any one of the first to the fourth aspects
wherein at least one of the upper rail and/or the lower rail
includes projection portion(s) projecting out towards the opposing
rail side in the vehicle up-down direction at the front end portion
or the rear end portion or both the front and rear end
portions.
[0019] In the vehicle seat of the fifth aspect, due to making the
separation distance between the pair of slide guides narrow,
sometimes cases arise in which the front end portion side or the
rear end portion side of the upper rail or both sides of the upper
rail bow towards the lower rail side when an overload is input to
the upper rail from the seat body side due, for example, the
vehicle being involved in a collision. In such cases the projection
portion(s) provided to the front end portion or the rear end
portion or both the front and rear end portions of at least one of
the upper rail and/or the lower rail suppress the bowing mentioned
above by making contact with the opposing rail in the vehicle
up-down direction (the lower rail or the upper rail). Accordingly,
seat rigidity performance can be secured during input of a large
load while still suppressing vibration of the seat body in normal
circumstances.
[0020] A vehicle seat of a sixth aspect of the present invention is
the vehicle seat of the fifth aspect wherein: the lower rail
includes a top wall whose bottom face faces towards the top face of
the upper rail and a bottom wall whose top face faces towards the
bottom face of the upper rail; the projection portion(s) are
provided to at least one of the top face side of the front end
portion of the upper rail and/or the bottom face side of the front
end portion of the top wall; and the projection portion(s) are
provided to at least one of the bottom face side of the rear end
portion of the upper rail and/or the top face side of the rear end
portion of the bottom wall.
[0021] In the vehicle seat of the sixth aspect, when the vehicle is
involved in a collision from behind, the front end portion side of
the upper rail bows upwards due to load input from the seat body,
and the projection portion(s) provided to at least one of the top
face side of the upper rail front end portion and/or the bottom
face side of the lower rail top wall front end portion make(s)
contact with the bottom face of the top wall of the lower rail or
the top face of the upper rail. Bowing of the upper rail front end
portion side is accordingly suppressed.
[0022] In such a situation, when the upper rail rear end portion
side bows downwards due to load input from the seat body, the
projection portion(s) provided to at least one of the bottom face
side of the upper rail rear end portion and/or the top face side of
the bottom wall rear end portion of the lower rail make(s) contact
with the top face of the bottom wall of the lower rail or the
bottom face of the upper rail. Bowing of the lower rail rear end
portion side is accordingly suppressed. The seat rigidity
performance when a vehicle is involved in a collision from behind
can accordingly be secured.
[0023] Note that bowing of the upper rail can be suppressed
irrespective of the sliding state of the upper rail with respect to
the lower rail when projection portions are provided to both the
top face side of the upper rail front end portion and the bottom
face side of the top wall front end portion of the lower rail and
to the bottom face side of the upper rail rear end portion and the
top face of the bottom wall rear end portion of the lower rail.
[0024] A vehicle seat of a seventh aspect of the present invention
is the vehicle seat of the fifth aspect wherein: the lower rail
includes a top wall whose bottom face faces towards the top face of
the upper rail and a bottom wall whose top face faces towards the
bottom face of the upper rail; the projection portion(s) are
provided to at least one of the bottom face side of the front end
portion of the upper rail and/or the top face side of the front end
portion of the bottom wall; and the projection portion(s) are
provided to at least one of the top face side of the rear end
portion of the upper rail and/or the bottom face side of the rear
end portion of the top wall.
[0025] In the vehicle seat of the seventh aspect, when the front
end portion side of the upper rail bows downwards due to load input
from the seat body when the vehicle is involved in a frontal
collision, the projection portion(s) provided to at least one of
the bottom face side of the upper rail front end portion and/or the
top face side of the bottom wall front end portion of the lower
rail make contact with the top face of the bottom wall of the lower
rail or the bottom face of the upper rail. Bowing of the upper rail
front end portion side is accordingly suppressed.
[0026] In such a situation, when the rear end portion side of the
upper rail bows upwards due to load input from the seat body, the
projection portion(s) provided to at least one of the top face side
of the upper rail rear end portion or the bottom face side of the
top wall rear end portion of the lower rail make(s) contact with
the bottom face of the top wall of the lower rail or the top face
of the upper rail. Bowing of the lower rail rear end portion side
is accordingly suppressed. Consequently, seat rigidity performance
when the vehicle is involved in a frontal collision can be
secured.
[0027] Note that bowing of the upper rail can be suppressed
irrespective of the sliding state of the upper rail with respect to
the lower rail when projection portions are provided to both the
bottom face side of the upper rail front end portion and the top
face side of the bottom wall front end portion of the lower rail
and to both the top face side of the upper rail rear end portion
and the bottom face side of the top wall rear end portion of the
lower rail.
[0028] A vehicle seat of an eighth aspect of the present invention
is the vehicle seat of the fifth aspect wherein: the seat
left-right direction end sides of the bottom face of the upper rail
are disposed closer to the lower rail than the seat left-right
direction central portion of the bottom face of the upper rail; and
the projection portion(s) are provided between the seat left-right
direction end sides of the bottom face of the upper rail and the
lower rail.
[0029] In the vehicle seat of the eighth aspect, the seat
left-right direction end sides of the bottom face of the upper rail
are disposed closer to the lower rail than the seat left-right
direction central portion of the bottom face of the upper rail and
projection portions are provided between the end sides and the
lower rail. The height dimension of the projection portions can
accordingly be made lower, enabling more compact and lighter
projection portions to be achieved.
[0030] A vehicle seat of a ninth aspect of the present invention is
the vehicle seat of the fifth aspect wherein: the lower rail
includes a rail body and bracket(s) for connecting the seat
front-rear direction end portions of the rail body to the vehicle
body; and the projection portion(s) are provided to the
bracket(s).
[0031] In the vehicle seat of the ninth aspect, due to providing
the projection portions to the bracket for connecting the rail body
of the lower rail to the vehicle body, the upper rail contacting
the projection portion when a large load is input to the seat body
can directly be supported by the vehicle body side rather than by
transmission through the rail body. Consequently, good seat
rigidity performance can be secured when a large load is input.
[0032] A vehicle seat of a tenth aspect of the present invention is
the vehicle seat of any one of the first to the fourth aspects
wherein the upper rail has a projection portion that projects
towards the lower rail side in the vicinity of below a connection
portion to the seat body.
[0033] In the vehicle seat of the tenth aspect, when the upper rail
bows towards the lower rail side due to load input from the seat
body side, such as when a vehicle is involved in a collision from
behind, the projection portion provided to the upper rail makes
contact with the lower rail. Bowing of the upper rail is
accordingly suppressed. Consequently seat rigidity performance when
the vehicle is involved in a collision from behind can be secured.
However, since the projection portion that makes contact with the
lower rail is provided to the upper rail in the vicinity of below
the connection portion to the seat body, the connection portion to
the seat body can be directly supported without being influenced by
bowing of the upper rail. Consequently, good supporting rigidity of
the seat body can be achieved by the projection portion.
Advantageous Effects of Invention
[0034] As explained above, in the vehicle seat according to the
first aspect of the present invention, vibration of the seat body
can be suppressed from occurring without providing an additional
separate device such as a dynamic damper.
[0035] In the vehicle seat according to the second aspect of the
present invention, the maximum siding amount of the upper rail with
respect to the lower rail can be set larger than the length
dimension of components such as the upper rail.
[0036] In the vehicle seat according to the third aspect of the
present invention, a simple structure is achieved that enables
unwanted interference of the rear upper projection portion with
respect to the rear lower projection portion and the second side
contact portion, and unwanted interference of the front upper
projection portion with the front lower projection portion and the
first side contact portion to be avoided.
[0037] In the vehicle seat according to the fourth aspect of the
present invention, the front lower projection portion and the rear
lower projection portion can be configured as a common component as
a detachment prevention stopper for preventing detachment of the
slide guides from the front-rear direction end portions of the
lower rail.
[0038] In the vehicle seat according to the fifth aspect of the
present invention, seat rigidity performance can be secured during
input of a large load while still suppressing vibration of the seat
body in normal circumstances.
[0039] In the vehicle seat according to the sixth aspect of the
present invention, seat rigidity performance when the vehicle is
involved in a collision from behind can be secured.
[0040] In the vehicle seat according to the seventh aspect of the
present invention, seat rigidity performance when the vehicle is
involved in a frontal collision can be secured.
[0041] In the vehicle seat according to the eighth aspect of the
present invention, the projection portion(s) can be configured so
as to be both compact and light weight.
[0042] In the vehicle seat according to the ninth aspect of the
present invention, good seat rigidity performance can be secured
when a large load is input.
[0043] In the vehicle seat according to the tenth aspect of the
present invention, good supporting rigidity of the seat body can be
achieved by the projection portion.
BRIEF DESCRIPTION OF DRAWINGS
[0044] FIG. 1 is a schematic side view illustrating a configuration
of relevant portions of a vehicle seat according to a first
exemplary embodiment of the present invention.
[0045] FIG. 2 is a schematic diagram of a slide rail that is a
configuration member of the vehicle seat illustrated in FIG. 1.
[0046] FIGS. 3A to 3F are vertical cross-sections, with FIG. 3A
corresponding to a vertical cross-section taken on line A-A of FIG.
1, FIG. 3B corresponding to a vertical cross-section taken on line
B-B of FIG. 1, FIG. 3C corresponding to a vertical cross-section
taken on line C-C of FIG. 1, FIG. 3D corresponding to a vertical
cross-section taken on line D-D of FIG. 1, FIG. 3E corresponding to
a vertical cross-section taken on line E-E of FIG. 1, and FIG. 3F
corresponding to a vertical cross-section taken on line F-F.
[0047] FIG. 4 is a perspective view of a slide guide that is a
configuration member of the slide rail illustrated in FIG. 1.
[0048] FIG. 5A is a schematic diagram for explaining a state in
which the upper rail of the slide rail according to the first
exemplary embodiment of the present invention has slid by a small
amount towards the seat rear side with respect to the lower rail,
and FIG. 5B is a vertical cross-section corresponding to line G-G
of FIG. 5A.
[0049] FIG. 6A is a schematic diagram for explaining a state in
which the upper rail has slid further towards the seat rear side
from the state illustrated in FIG. 5, and FIG. 6B is a vertical
cross-section corresponding to line H-H of FIG. 6A.
[0050] FIG. 7A is a schematic diagram for explaining a state in
which the upper rail has slid to the maximum extent towards the
seat rear side, and FIG. 7B is a vertical cross-section
corresponding to line I-I of FIG. 7A.
[0051] FIG. 8 is a schematic diagram illustrating a neutral state,
a rear-most state and a front-most state of a slide rail according
to a first exemplary embodiment of the present invention.
[0052] FIG. 9 is a chart for explaining vibration of a vehicle seat
and frequencies such as a bending resonance frequency of a vehicle
body.
[0053] FIG. 10 is a graph illustrating relationships between
inertance and front-rear direction resonance frequencies of a seat
body.
[0054] FIG. 11 is a schematic diagram illustrating a neutral state,
a rear-most state and a front-most state of a related slide
rail.
[0055] FIG. 12 is schematic diagram illustrating a neutral state, a
rear-most state and a front-most state in a related slide rail in
which the separation distance of a pair of slide guides has been
narrowed.
[0056] FIG. 13 is schematic diagram illustrating a neutral state, a
rear-most state and a front-most state in a related slide rail in
which the rail length has been extended.
[0057] FIG. 14 is schematic diagram illustrating a neutral state, a
rear-most state and a front-most state in a related slide rail in
which the rail length has been shortened.
[0058] FIG. 15 is schematic diagram illustrating a neutral state, a
rear-most state and a front-most state in a slide rail according to
the first exemplary embodiment of the present invention in which
the rail length has been shortened.
[0059] FIG. 16 is a table comparing slide rails according to the
first exemplary embodiment of the present invention and related
slide rails.
[0060] FIG. 17A is a vertical cross-section of a slide rail
according to a first modified example of the first exemplary
embodiment of the present invention, FIG. 17B is a vertical
cross-section of a lower rail of the slide rail, FIG. 17C is a
vertical cross-section of an upper rail of the slide rail, and FIG.
17D is a face-on view of the slide guide of the slide rail.
[0061] FIG. 18A is a vertical cross-section illustrating a modified
example of the upper rail illustrated in FIG. 17C, and FIG. 18B is
another modified example of the upper rail illustrated in FIG.
17C.
[0062] FIG. 19A is a vertical cross-section of a slide rail
according to a second modified example of the first exemplary
embodiment of the present invention, FIG. 19B is a vertical
cross-section of a lower rail of the slide rail, FIG. 19C is a
vertical cross-section of an upper rail of the slide rail, and FIG.
19D is a face-on view of the slide guide of the slide rail.
[0063] FIG. 20A is a vertical cross-section of a slide rail
according to a third modified example of the first exemplary
embodiment of the present invention, FIG. 20B is a vertical
cross-section of a lower rail of the slide rail, FIG. 20C is a
vertical cross-section of an upper rail of the slide rail, and FIG.
20D is a face-on view of the slide guide of the slide rail.
[0064] FIG. 21A is a vertical cross-section of a slide rail
according to a fourth modified example of the first exemplary
embodiment of the present invention, FIG. 21B is a vertical
cross-section of a lower rail of the slide rail, FIG. 21C is a
vertical cross-section of an upper rail of the slide rail, and FIG.
21D is a face-on view of the slide guide of the slide rail.
[0065] FIG. 22 is a schematic diagram of a slide rail that is a
configuration member of a vehicle seat according to a second
exemplary embodiment of the present invention.
[0066] FIG. 23A is a vertical cross-section corresponding to line
J-J in FIG. 22, and FIG. 23B is a vertical cross-section
corresponding to line K-K in FIG. 22.
[0067] FIG. 24 is a schematic side view illustrating a
configuration of relevant portions of a vehicle seat according to
the second exemplary embodiment of the present invention, and is an
explanatory diagram of a load input state when a vehicle is
involved in a collision from behind.
[0068] FIG. 25A is vertical cross-section corresponding to FIG.
23A, illustrating a state in which the top face of the upper rail
has made contact with projection portions on the lower rail front
end portion, and FIG. 25B is a vertical cross-section corresponding
to FIG. 23B, illustrating a state in which the bottom face of the
upper rail has made contact with a projection portion of the lower
rail rear end portion.
[0069] FIG. 26 is a schematic diagram for explaining a state in
which the upper rail of the slide rail illustrated in FIG. 23 has
bowed.
[0070] FIG. 27A is a schematic diagram for explaining a state in
which the upper rail of a related slide rail has bowed, and FIG.
27B is a schematic diagram for explaining a case in which the slide
guide separation of the slide rail illustrated in FIG. 27A has been
narrowed and the upper rail is in a bowed state.
[0071] FIG. 28 is a graph illustrating characteristics of load
against bowing for a slide rail according to the second exemplary
embodiment of the present invention and related slide rails.
[0072] FIG. 29 is a perspective view illustrating a first modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0073] FIG. 30 is a perspective view illustrating a second modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0074] FIG. 31 is a perspective view illustrating a third modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0075] FIG. 32 is a perspective view illustrating a fourth modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0076] FIG. 33 is a perspective view illustrating a fifth modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0077] FIG. 34 is a perspective view illustrating a sixth modified
example of a projection portion according to the second exemplary
embodiment of the present invention.
[0078] FIG. 35 is a perspective view illustrating a seventh
modified example of a projection portion according to the second
exemplary embodiment of the present invention.
[0079] FIG. 36 is a schematic diagram of a slide rail that is a
configuration member of a vehicle seat according to a third
exemplary embodiment of the present invention.
[0080] FIG. 37A is a vertical cross-section corresponding to line
L-L in FIG. 36, and FIG. 37B is a vertical cross-section
corresponding to line M-M in FIG. 36.
[0081] FIG. 38 is a schematic side view illustrating a
configuration of relevant portions of a vehicle seat according to
the third exemplary embodiment of the present invention, and is an
explanatory diagram of a load input state when a vehicle is
involved in a frontal collision.
[0082] FIG. 39A is vertical cross-section corresponding to FIG.
37A, illustrating a state in which the bottom face of the upper
rail has made contact with a projection portion on the lower rail
front end portion, and FIG. 39B is a vertical cross-section
corresponding to FIG. 37B, illustrating a state in which the top
face of the upper rail has made contact with projection portions of
the lower rail rear end portion.
[0083] FIG. 40 is a vertical cross-section illustrating a modified
example of an attachment position of a projection portion according
to the second exemplary embodiment and the third exemplary
embodiment of the present invention.
[0084] FIG. 41 is a vertical cross-section illustrating another
modified example of an attachment position of the projection
portion according to the second exemplary embodiment and the third
exemplary embodiment of the present invention.
[0085] FIG. 42 is a schematic diagram illustrating a configuration
of relevant portions of a vehicle seat according to the fourth
exemplary embodiment of the present invention.
[0086] FIG. 43 is an enlarged diagram of a portion of FIG. 42.
[0087] FIG. 44 is a graph illustrating characteristics of load
against bowing for slide rails according to the second exemplary
embodiment and the fourth exemplary embodiment of the present
invention.
[0088] FIG. 45 is a schematic diagram illustrating a configuration
of relevant portions of the vehicle seat according to the fifth
exemplary embodiment of the present invention.
[0089] FIG. 46A corresponds to a vertical cross-section taken on
line N-N in FIG. 45, FIG. 46B corresponds to a vertical
cross-section taken on line O-O in FIG. 45, FIG. 46C corresponds to
a vertical cross-section taken on line P-P in FIG. 45, and FIG. 46D
corresponds to a vertical cross-section taken on line Q-Q in FIG.
45.
DESCRIPTION OF EMBODIMENTS
First Exemplary Embodiment
[0090] Explanation follows regarding a vehicle seat 10 according to
a first exemplary embodiment of the present invention, with
reference to FIG. 1 to FIG. 21. In the drawings arrow UP indicates
the top direction of the vehicle seat 10, arrow FR indicates the
front direction of the vehicle seat 10, and arrow RH indicates the
vehicle seat right hand side direction.
[0091] As shown in FIG. 1, the vehicle seat 10 according to the
first exemplary embodiment is equipped with a seat body 12. The
seat body 12 includes a seat cushion 14 for supporting the bottom
of a seated occupant and a seat back 16 for supporting the back
region of the seated occupant. The seat cushion 14 includes a frame
member of a seat cushion frame 18, and a seat back frame 20, which
is a frame member of the seat back 16, is connected to a rear end
portion of the seat cushion frame 18. A lower end portion of the
seat cushion frame 18 is also connected to a floor 24 of a vehicle
body through a left and right pair of slide rails 22. Only the
slide rail 22 disposed on the left hand side of the vehicle seat 10
is illustrated in FIG. 1. FIG. 2 is a schematic diagram
illustrating the slide rail 22.
[0092] Each of the slide rails 22 includes an upper rail 26
attached to a lower end portion of the seat cushion frame 18, and a
lower rail 28 that is fixed to the floor 24. The lower rail 28 has
an elongated lower rail body 30 (rail body) configuring a main body
section of the lower rail 28. The lower rail body 30 is disposed in
an orientation aligned along the vehicle seat 10 front-rear
direction (the seat front-rear direction). The front end side and
the rear end side of the lower rail body 30 are connected to the
floor 24 through a pair of front and rear brackets 32, 34.
[0093] As shown in FIG. 3, the lower rail body 30 is formed in a
substantially rectangular cross-section tube shape (a substantially
C-shaped cross-section), formed with a slit 36 in a left-right
direction central portion of the top wall. The slit 36 extends
along the length direction of the lower rail body 30. An elongated
upper rail body 38 configuring a main body section of the upper
rail 26 is housed at the inside of the lower rail body 30.
[0094] The upper rail body 38 is formed with a substantially
W-shaped cross-section and is disposed oriented with the length
direction aligned along the seat front-rear direction. A connection
portion 40 to the seat body 12 extends out upwards from a
left-right direction central portion at an upper portion of the
upper rail body 38. The connection portion 40 passes through the
slit 36 of the lower rail body 30 so as to project out upwards from
the lower rail body 30.
[0095] As shown in FIG. 2, and the cross-sections on line C-C and
on line D-D of FIG. 3, a pair of slide guides 42, 44 are disposed
in a row along the seat front-rear direction in a gap between the
lower rail body 30 and the upper rail body 38. Each of the slide
guides 42, 44 includes a guide body 46 formed by sheet metal
folding (see FIG. 5).
[0096] Plural balls 48 are rotatably mounted to top portions and
bottom portions of the guide body 46. The plural balls 48 mounted
to the top portion of the guide body 46 are interposed between the
top wall of the lower rail body 30 and the upper face of the upper
rail body 38. The plural balls 48 mounted to the bottom portions of
the guide body 46 are interposed between the bottom wall of the
lower rail body 30 and the bottom face of the upper rail body 38.
Each of the upper rail bodies 38 is accordingly supported by the
lower rail body 30 through the balls 48 of the front and rear pair
of slide guides 42, 44. Each of the upper rails 26 is hence capable
of sliding in the seat front-rear direction with respect to the
respective lower rail 28.
[0097] As shown in the cross-section on line A-A of FIG. 3, a front
lower projection portion 50 formed in a block shape is provided at
a front end portion of the lower rail body 30. The front lower
projection portion 50 is formed as a separated body from the lower
rail body 30, and fixed to the bottom wall of the lower rail body
30 so as to project upwards from the bottom wall of the lower rail
body 30. The front lower projection portion 50 is disposed further
to the right hand side than a seat left-right direction central
portion of the lower rail body 30.
[0098] As shown in the cross-section on line B-B of FIG. 3, a front
upper projection portion 52 is provided to an intermediate portion
of the upper rail body 38 further to the front end side of the
upper rail body 38 than the front-rear direction central portion of
the upper rail body 38. The front upper projection portion 52 is
formed by cutting around and projecting out a portion at a
left-right direction intermediate portion of the upper rail body
38, and is disposed further to the seat left hand side than the
seat left-right direction central portion of the upper rail body
38.
[0099] As shown in the cross-section on line C-C of FIG. 3, a right
hand side contact portion 54 (first side contact portion) is
provided to the guide body 46 of the slide guide 42 on the seat
front side. The right hand side contact portion 54 is formed by a
portion on the bottom wall of the guide body 46 pressed out upwards
with a trapezoidal cross-section profile. The right hand side
contact portion 54 is disposed further to the seat right hand side
than the seat left-right direction central portion of the upper
rail body 38 and the lower rail body 30. The right hand side
contact portion 54 corresponds to the front lower projection
portion 50.
[0100] As shown in the cross-section taken on line D-D of FIG. 3, a
left hand side contact portion 56 (second side contact portion) is
provided on the guide body 46 of the slide guide 44 at the seat
rear side. The left hand side contact portion 56 is configured
basically the same as the right hand side contact portion 54 of the
slide guide 42, however the left hand side contact portion 56 is
disposed further to the seat left hand side than the left-right
direction central portion of the upper rail body 38 and the lower
rail body 30, and is left-right symmetrical to the right hand side
contact portion 54. The left hand side contact portion 56
corresponds to the front upper projection portion 52. In the
present exemplary embodiment the pair of slide guides 42, 44 are
configured exactly the same as each other.
[0101] As shown in the cross-section taken on line E-E of FIG. 3, a
rear upper projection portion 58 is provided to an intermediate
portion of the upper rail body 38, further to the rear end side of
the upper rail body 38 than the front-rear direction central
portion of the upper rail body 38. The rear upper projection
portion 58 is configured basically the same as the front upper
projection portion 52, however the rear upper projection portion 58
is disposed further to the seat right hand side than the seat
left-right direction central portion of the upper rail body 38, and
is left-right symmetrical to the front upper projection portion 52.
The rear upper projection portion 58 corresponds to the front lower
projection portion 50 and the right hand side contact portion
54.
[0102] As shown in the cross-section taken on line F-F of FIG. 3, a
rear lower projection portion 60 formed in a block shape is
provided to a rear end portion of the lower rail body 30. The rear
lower projection portion 60 is configured basically the same as the
front lower projection portion 50, however the rear lower
projection portion 60 is disposed further to the seat left hand
side than the seat left-right direction central portion of the
lower rail body 30, and is left-right symmetrical to the front
lower projection portion 50. The rear lower projection portion 60
corresponds to the front upper projection portion 52 and the left
hand side contact portion 56.
[0103] In the first exemplary embodiment, as shown in FIG. 2, the
separation between the front upper projection portion 52 and the
rear upper projection portion 58 is set so as to be narrower than
the separation between the front lower projection portion 50 and
the rear lower projection portion 60. In a state in which the upper
rail 26 is disposed at the center of its sliding range with respect
to the lower rail 28 (referred to below as the neutral state), the
slide guide 42 on the seat front side is disposed at the center
between the front lower projection portion 50 and the rear upper
projection portion 58, and the slide guide 44 on the seat rear side
is disposed in the center between the front upper projection
portion 52 and the rear lower projection portion 60. In the neutral
state the front upper projection portion 52 is disposed in front of
and in the vicinity of the slide guide 42 on the seat front side,
and the rear upper projection portion 58 is disposed to the rear of
and in the vicinity of the slide guide 44 on the seat rear
side.
[0104] When the upper rail 26 is slid from the neutral state
towards the seat rear side with respect to lower rail 28, as shown
in FIG. 5A, the front upper projection portion 52 and the slide
guide 42 on the seat front side overlap with each other as viewed
from the side. However, when this occurs interference between the
two components is avoided by, as shown in FIG. 5B, disposing the
front upper projection portion 52 and the right hand side contact
portion 54 displaced from each other along the seat left-right
direction.
[0105] When the upper rail 26 slides further from the state
illustrated in FIG. 5A towards the seat rear side with respect to
the lower rail 28, the rear upper projection portion 58 and the
rear lower projection portion 60 then overlap with each other when
viewed from the side, as shown in FIG. 6A. However, when this
occurs interference between the two components is avoided by, as
shown in FIG. 6B, disposing the rear upper projection portion 58
and the rear lower projection portion 60 displaced from each other
along the seat left-right direction.
[0106] When the upper rail 26 slides further from the state
illustrated in FIG. 6A towards the seat rear side with respect to
the lower rail 28, as shown in FIG. 7A, the front upper projection
portion 52 approaches the vicinity of the rear lower projection
portion 60, and the left hand side contact portion 56 of the slide
guide 44 on the seat rear side is sandwiched between the front
upper projection portion 52 and the rear lower projection portion
60 (see FIG. 7B). The upper rail 26 is accordingly restricted from
sliding towards the seat rear side with respect to the lower rail
28 (referred to below as the rear-most state).
[0107] Similarly, when the upper rail 26 has been slid towards the
seat front side with respect to the lower rail 28, the right hand
side contact portion 54 of the slide guide 42 on the seat front
side is sandwiched between the rear upper projection portion 58 and
the front lower projection portion 50, restricting sliding of the
upper rail 26 towards the seat front side with respect to the lower
rail 28 (referred to below as the front-most state).
[0108] Namely, in the first exemplary embodiment, as shown in FIG.
8, the sum of sliding amount s1 of the upper rail 26 from the
neutral state to the rear-most state and sliding amount s2 from the
neutral state to the front-most state is a maximum slide amount S
of the upper rail 26 with respect to the lower rail 28. A
separation distance L between the seat front-rear direction central
portion of the slide guide 42 on the seat front side and the seat
front-rear direction central portion of the slide guide 44 on the
seat rear side is set to be narrower than half of the maximum slide
amount S (L<S/2). In the first exemplary embodiment, the
separation distance L is set narrower than half the total length of
the upper rail 26 and the lower rail 28.
[0109] Explanation follows regarding operation and effects of the
first exemplary embodiment.
[0110] In the vehicle seat 10 configured as described above, the
separation distance L of each of the front and rear pairs of the
slide guides 42, 44 is made narrower than a specific value
(narrower than half the maximum slide amount S of the upper rail 26
with respect to the lower rail 28). The supporting rigidity to the
seat body 12 from the vehicle body is therefore lowered, lowering
the front-rear direction resonance frequency of the seat body 12.
The front-rear direction resonance frequency of the seat body 12
can accordingly be shifted away from, for example the resonance
frequency of the vehicle body such as during vehicle engine idling
(see FIG. 9). Consequently, vibration can be suppressed from
occurring in the seat body 12 without adding an additional separate
device such as a dynamic damper. Accordingly, the vehicle seat 10
can at low cost raise the noise and vibration performance
(capability to suppress vibration and vibration noise, referred to
below as NV performance).
[0111] FIG. 10 is a line graph illustrating measurement results of
front-rear direction resonance frequency of the seat body 12 when
the separation distance L of the slide guides 42, 44 is changed in
3 stages (wide, normal, narrow). It can be seen from FIG. 10 that
the front-rear direction resonance frequency of the seat body 12
can be greatly lowered by making the separation distance L of the
slide guides 42, 44 narrower. Accordingly, in the vehicle seat 10,
the front-rear direction resonance frequency of the seat body 12
can for example be shifted from the resonance frequency of the
vehicle body such as during idling, and vibrations can be
suppressed from occurring in the seat body 12.
[0112] However, in the vehicle seat 10, the upper rail 26 is
restrained from sliding towards the seat rear side with respect to
the lower rail 28 by the left hand side contact portion 56 provided
to the slide guide 44 on the seat rear side being sandwiched
between the front upper projection portion 52 disposed further to
the seat front side than the front-rear direction central portion
of the upper rail 26 and the rear lower projection portion 60
provided to the rear end portion of the lower rail 28. The upper
rail 26 is also restrained from sliding towards the seat front side
with respect to the lower rail 28 by the right hand side contact
portion 54 provided to the slide guide 42 on the seat front side
being sandwiched between the rear upper projection portion 58
disposed further to the seat rear side of the front-rear direction
central portion of the upper rail 26 and the front lower projection
portion 50 provided to the front end portion of the lower rail
28.
[0113] Consequently, in the vehicle seat 10 both the sliding amount
s1 of the upper rail 26 from the neutral state to the rear-most
state and the sliding amount s2 of the upper rail 26 from the
neutral state to the front-most state can be set large. This
enables the maximum slide amount S (s1+s2) of the upper rail 26
with respect to the lower rail 28 to also be set larger than the
overall length of each of the upper rails 26 and each of the lower
rails 28. Accordingly the vehicle seat 10 can solve various of the
problems occurring in slide rails of related vehicle seats.
[0114] Namely, in a case when one projection portion 202 is
provided at the front-rear direction central portion of the upper
rail body 38 as in the related slide rail 200 shown in FIG. 11, the
maximum slide amount S of the upper rail 26 with respect to the
lower rail 28 can only be set at about twice the separation
distance L of the slide guides 42, 44. Hence when the separation
distance L of the slide guides 42, 44 is narrowed in order to raise
NV performance, as shown in FIG. 12, the maximum slide amount S of
the upper rail 26 (namely of the seat body 12) is also narrowed. In
the related slide rail 200 it is therefore not possible to both
raise NV performance and maintain the maximum slide amount S.
[0115] However regarding this aspect, in the slide rail 22 of the
vehicle seat 10, since a large maximum slide amount S of the upper
rail 26 with respect to the lower rail 28 can be set even when the
separation distance L of the slide guides 42, 44 is narrowed,
raised NV performance and maintained maximum slide amount S can be
both achieved at the same time.
[0116] Furthermore, in the related slide rail 200, when the maximum
slide amount S is increased in order to raise comfort performance
for a seated occupant, as shown in FIG. 13, the overall length of
the upper rail 26 and the lower rail 28 needs to be lengthened,
increasing the width of the mounting base for the slide rails in
the vehicle compartment. Accordingly various problems arise, such
as the foot space available for an occupant seated on the rear seat
is reduced, a rear seated occupant is less able to get in and out
(impeded, made awkward), fuel efficiency is reduced due to the
increase in weight of the slide rails, material cost is increased,
and product quality is adversely impacted due to bare metal slide
rails being exposed to view inside the vehicle compartment (worse
appearance).
[0117] Regarding these aspects, in the slide rail 22 of the vehicle
seat 10, since the maximum slide amount S is increased without
increasing the overall length of the lower rail 28 and the upper
rail 26, the front seat comfort can be raised while not adversely
impacting on the comfort of the rear seats or increasing
weight.
[0118] Or to put it another way, in order to reduce weight and
material cost and improve rear seat comfort there is a need to
shorten the overall length of the upper rail 26 and the lower rail
28 in the related slide rail 200, as shown in FIG. 14, however in
such a case the maximum slide amount S is also shortened.
[0119] Regarding this aspect, with the slide rail 22 of the vehicle
seat 10, the overall length of the upper rail 26 and the lower rail
28 can be shortened while still maintaining the maximum slide
amount S, as shown in FIG. 15. Accordingly, such improvements as a
reduction in weight can be achieved while still maintaining the
maximum slide amount S.
[0120] Note that FIG. 16 is a table of comparisons of the slide
rail 22 of the vehicle seat 10 (the structure such as illustrated
in FIG. 8 and FIG. 15) against the related vehicle seat slide rail
200 (the structure illustrated in FIG. 11 to FIG. 14). It is clear
from FIG. 16 that the slide rail structure of the vehicle seat 10
is good in all aspects of NV performance, weight, maximum slide
amount, and rear seat comfort performance.
[0121] Furthermore, in the slide rail structure of the vehicle seat
10, the front upper projection portion 52, the rear lower
projection portion 60 and the left hand side contact portion 56 are
disposed further to the seat left hand side than the seat
left-right direction central portions of the upper rail 26 and the
lower rail 28, and the rear upper projection portion 58, the front
lower projection portion 50 and the right hand side contact portion
54 are disposed further to the seat right hand side than the seat
left-right direction central portions of the upper rail 26 and the
lower rail 28. Accordingly, a simple structure is achieved that
enables unwanted interference of the rear upper projection portion
58 with respect to the rear lower projection portion 60 and the
left hand side contact portion 56, and unwanted interference of the
front upper projection portion 52 with the front lower projection
portion 50 and the right hand side contact portion 54 to be
avoided.
[0122] In the slide rail structure of the vehicle seat 10, the
front lower projection portion 50 is provided at a front end
portion of the lower rail 28, and the rear lower projection portion
60 is provided at a rear end portion of the lower rail 28.
Accordingly, the front lower projection portion 50 and the rear
lower projection portion 60 can be configured as a common component
as a detachment prevention stopper for preventing detachment of the
slide guides 42, 44 from at the front-rear direction end portions
of the lower rail 28, respectively.
[0123] The slide rail 22 according to the first exemplary
embodiment exhibits similar capabilities when used with the upper
rail 26 and the lower rail 28 turned upside down. However, in such
a configuration the detachment prevention stoppers of the slide
guides 42, 44 need to be provided to the two front and rear end
portions of the upper rail 26 disposed on the bottom side.
[0124] Explanation follows regarding a modified example of the
slide rail 22 according to the first exemplary embodiment.
First Modified Example
[0125] FIG. 17A is a schematic vertical cross-section illustrating
a configuration of a slide rail 62 according to a first modified
example of the above first exemplary embodiment. The slide rail 62
is configured basically the same as the slide rail 22 according to
the first exemplary embodiment, however it differs therefrom in
that a rear lower projection portion 64 and a front upper
projection portion 66 are configured in place of the rear lower
projection portion 60 and the front upper projection portion 52 of
the first exemplary embodiment.
[0126] As shown in FIG. 17B, the rear lower projection portion 64
is formed by a portion of the bottom wall of the lower rail 28
pressed out upwards with a trapezoidal cross-section profile. As
shown in FIG. 17C, the front upper projection portion 66, similarly
to the front upper projection portion 52, is formed by cutting
around and projecting out a portion of the upper rail 26, however
the direction of cutting around and projecting out is different to
that of the front upper projection portion 52.
[0127] In the first modified example too, sliding of the upper rail
26 towards the seat rear side with respect to the lower rail 28 is
restricted by a left hand side contact portion 56 (see FIG. 17D)
provided to the slide guide 44 being sandwiched between the front
upper projection portion 66 and the rear lower projection portion
64.
[0128] Configuration may be made such that a front upper projection
portion 68 as illustrated in FIG. 18A, or a front upper projection
portion 70 as illustrated in FIG. 18B, is employed in place of the
front upper projection portion 66. The front upper projection
portions 68, 70 are formed by portions of the upper rail 26 pressed
out towards the inside.
Second Modified Example
[0129] A schematic vertical cross-section of a configuration of a
slide rail 72 according to a second modified example of the first
exemplary embodiment is illustrated in FIG. 19A. The slide rail 72
is configured basically the same as the slide rail 22 according to
the first exemplary embodiment, however a rear lower projection
portion 74, a front upper projection portion 76 and a right hand
side contact portion 78 differ from the rear lower projection
portion 60, the front upper projection portion 52 and the right
hand side contact portion 56 of the first exemplary embodiment.
[0130] As shown in FIG. 19B the rear lower projection portion 74 is
formed by bending a portion on the top wall of the lower rail 28 so
as to face downwards. As shown in FIG. 19C, the front upper
projection portion 76 is formed by cutting around a portion of the
upper rail 26 and projecting it upwards. As shown in FIG. 19D, the
left hand side contact portion 78 is provided in the top wall of
the guide body 46 of the slide guide 44.
[0131] In the second modified example too, the upper rail 26 is
restricted from sliding with respect to the lower rail 28 towards
the seat rear side by the left hand side contact portion 78
provided to the slide guide 44 being sandwiched between the front
upper projection portion 76 and the rear lower projection portion
74.
Third Modified Example
[0132] FIG. 20A illustrates a schematic vertical cross-section of a
configuration of a slide rail 82 according to a third modified
example of the first exemplary embodiment. The slide rail 82 is
configured basically the same as the slide rail 22 according to the
first exemplary embodiment, however a rear lower projection portion
82, a front upper projection portion 84 and a slide guide 86 differ
from the rear lower projection portion 60, the front upper
projection portion 52 and the slide guide 46 according to the first
exemplary embodiment.
[0133] As shown in FIG. 20B, the rear lower projection portion 82
is formed by cutting around and projecting out a portion of the
side wall of a lower rail 28 towards the inside of the lower rail
28. As shown in FIG. 20C, the front upper projection portion 84 is
formed by cutting around and projecting out a portion at the
left-right direction end portion of the upper rail 26 towards the
outside. As shown in FIG. 20D, the slide guide 86 is configured
without the side wall and the top wall at the right hand side of
the guide body 46, with a left hand side contact portion 88
configured by a top-bottom direction intermediate portion of the
left hand side wall.
[0134] In the third modified example too, the upper rail 26 is
restricted from sliding with respect to the lower rail 28 towards
the seat rear side by the left hand side contact portion 88
provided to the slide guide 86 being sandwiched between the front
upper projection portion 84 and the rear lower projection portion
82.
Fourth Modified Example
[0135] FIG. 21A is a schematic vertical cross-section illustrating
a configuration of a slide rail 90 according to a fourth modified
example of the first exemplary embodiment. The slide rail 90 is
configured basically the same as the slide rail 22 according to the
first exemplary embodiment, however two rear lower projection
portions 60, 92 and two front upper projection portions 94, 96 are
provided. A slide guide 98 of the slide rail 90 is also configured
so as to be separated on the left and right.
[0136] As shown in FIG. 21B, the rear lower projection portion 92
is formed by cutting out around and projecting a portion of the top
wall of the lower rail 28 out downwards. As shown in FIG. 21C, the
front upper projection portions 94, 96 are formed by cutting around
and projecting out portions of the upper rail 26. As shown in FIG.
20D, the slide guide 98 has a guide body 46 that is divided into a
right hand side member 46R and a left hand side member 46L. An
upper side contact portion 100 is configured at an end portion on
the top wall of the right hand side member 46R. A lower side
contact portion 102 is also formed to an end portion of the bottom
wall of the left hand side member 46L so as to bend around
upwards.
[0137] In the fourth modified example, the upper rail 26 is
restricted from sliding with respect to the lower rail 28 towards
the seat rear side by the upper side contact portion 100 provided
to the right hand side member 46R of the slide guide 98 being
sandwiched between the front upper projection portion 94 and the
rear lower projection portion 92, and the lower side contact
portion 102 provided to the left hand side member 46L being
sandwiched between the front upper projection portion 96 and the
rear lower projection portion 60.
[0138] The first modified example is most preferable out of the
four modified examples described above from the perspectives of
strength and ease of manufacture. In the above four modified
examples reference has not been made to the front lower projection
portion and the rear upper projection portion, however the front
lower projection portion and the rear upper projection portion are
configured so as to be left-right symmetrical to the rear lower
projection portion and the front upper projection portion, and
similar structures can be employed to those of the above four
modified examples.
[0139] Explanation next follows regarding another exemplary
embodiment of the present exemplary embodiment. Note that
configuration and operation that is basically the same as that of
the first exemplary embodiment is appended with the same reference
numerals to those of the first exemplary embodiment and further
explanation thereof is omitted.
Second Exemplary Embodiment
[0140] FIG. 22 is a schematic diagram illustrating a slide rail 112
that is a configuration member of a vehicle seat 110 (see FIG. 24)
according to a second exemplary embodiment of the present
invention. FIG. 23A is a vertical cross-section corresponding to
line J-J in FIG. 22, and FIG. 23B is a vertical cross-section
corresponding to line K-K in FIG. 22.
[0141] The slide rail 112 is of basically the same configuration as
that of the slide rail 22 according to the first exemplary
embodiment, however in the slide rail 112, a left and right pair of
projection portions 114 employed as load bearings are provided to a
front end portion of the lower rail body 30, and a projection
portion 116 employed as a load bearing is provided to a rear end
portion of the lower rail body 30. For ease of explanation, the
front lower projection portion 50, the rear lower projection
portion 60, the front upper projection portion 52 and the rear
upper projection portion 58 are omitted from illustration in FIG.
22 to FIG. 27.
[0142] The left and right pair of projection portions 114 provided
at the front end portion of the lower rail body 30 are each formed
in a block shape, and fixed by welding to a top wall 30A of the
lower rail body 30. The projection portions 114 project out from
the bottom face side of the top wall 30A (the side facing towards
the top face of the upper rail body 38), and each bottom end
thereof faces towards the top face of the upper rail body 38 with a
separation thereto of specific gap H1.
[0143] The projection portion 116 provided to the rear end portion
of the lower rail body 30 is also formed in a block shape, and
fixed by welding to the top face of a bottom wall 30B of the lower
rail body 30 (the face facing towards the bottom face of the upper
rail body 38). The top end of the projection portion 116 faces
towards the bottom face of the upper rail body 38 with a separation
thereto of a specific gap H2.
[0144] The "top face of the upper rail body 38" is the "top face of
the upper rail 26", and the "bottom face of the upper rail body 38"
is the "bottom face of the upper rail 26". The "top wall 30A of the
lower rail body 30" is the "top wall of the lower rail 28", and the
"bottom wall 30B of the lower rail body 30" is the "bottom wall of
the lower rail 28".
[0145] As shown in FIG. 23A, the gap H1 between the bottom end of
the projection portion 114 and the top face of the upper rail body
38 is set so as to be narrower than a gap H3 between the top wall
30A of the lower rail body 30 and the upper rail body 38. As shown
in FIG. 23B, the gap H2 between the top end of the projection
portion 116 and the bottom face of the upper rail body 38 is set so
as to be narrower than a gap H4 between the bottom wall 30B of the
lower rail body 30 and the upper rail body 38. The gap H1 and the
gap H2 are also set with equivalent dimensions to each other.
[0146] Explanation follows regarding operation and effect of the
second exemplary embodiment.
[0147] In the vehicle seat 110 according to the second exemplary
embodiment, when the vehicle is involved in a collision from behind
then, as shown in FIG. 24, an overload F1 is input towards the
vehicle rear with respect to the seat back 16 of the seat body 12
from force due to inertia of a seated occupant. In such a situation
an overload F2 is input upwards to the front end portion side of
the upper rail 26. When the front end portion side of the upper
rail body 38 bows upwards due to the load F2, as shown in FIG. 25A,
the projection portion 114 provided to the front end portion of the
top wall 30A of the lower rail body 30 makes contact with the top
face of the upper rail body 38. Bowing of the front end portion
side of the upper rail body 38 is accordingly suppressed (see the
intermittent line of FIG. 26).
[0148] In such a situation the rear end portion side of the upper
rail 26 is also, as shown in FIG. 24, input with a large downwards
load F3. The rear end portion side of the upper rail body 38 is
bowed towards the bottom side by the load F3, and the projection
portion 116 provided to the rear end portion of the bottom wall 30B
of the lower rail body 30 makes contact with the bottom face of the
upper rail body 38. The rear end portion side of the upper rail
body 38 is accordingly suppressed from bowing (see the intermittent
line of FIG. 26).
[0149] The vehicle seat 110 according to the second exemplary
embodiment is accordingly capable of suppressing bowing of the
upper rail 26 when involved in a collision from behind (when a
large load is input), and support rigidity (strength requirement)
of the seat body 12 can thereby be secured during a collision from
behind. Similarly to the slide rail 22 according to the first
exemplary embodiment, the supporting rigidity during normal
operation of the seat body 12 can be lowered by narrowing the
separation between the front and rear pair of slide guides 42, 44.
Accordingly, in the vehicle seat 110 the NV performance is raised
and also strength requirements during a collision from behind can
also be addressed.
[0150] Namely, in a related slide rail 300W as shown in FIG. 27A,
the NV performance can be raised by narrowing the separation
between a pair of slide guides 42, 44, such as in the slide rail
300N illustrated in FIG. 27B. However, in such a case the bowing
deformation amount of the upper rail 26 during a collision from
behind becomes large, as shown by the intermittent line in FIG. 27A
and FIG. 27B, with the load imparted before the upper rail 26 makes
contact with the lower rail 28 getting smaller. This accordingly
contradicts strength requirements during a collision from
behind.
[0151] Regarding this perspective, the slide rail 112 according to
the second exemplary embodiment can secure the strength
requirements during a collision from behind as described above.
FIG. 28 is a graph illustrating a relationship between the input
load to the upper rail 26 during a collision from behind and the
deflection (bowing) of the upper rail 26. In FIG. 28, the
deflection of the upper rail 26 until the upper rail 26 of the
slide rail 112 makes contact with the projection portions 114, 116
is indicated by X1, the deflection of the upper rail 26 of the
slide rail 300W and the slide rail 300N (NV designed structure)
until making contact with the lower rail 28 is indicated by X2. It
can be seen from FIG. 28 that in the slide rail 300N, the
deflection of the upper rail 26 during collision from behind is
large, with this being detrimental to strength requirements. It can
also be seen from FIG. 28 that the slide rail 112 has a small
amount of deflection of the upper rail 26 during a collision from
behind, and a similar load is generated to that of the slide rail
300W (having a wide spacing between the slide guides 42, 44).
[0152] Namely, the invention implemented by the slide rail 112
according to the second exemplary embodiment addresses the
"non-linearity of load against bowing characteristics" like those
shown in FIG. 28. Accordingly, both improvement of NV performance
and strength requirements during a collision from behind, which are
contradicting objectives, can be solved using an extremely simple
configuration.
[0153] Configuration is made in the second exemplary embodiment
with the projection portion 116 formed in a block shape fixed by
welding to the rear end portion of the bottom wall 30B of the lower
rail body 30, however the present exemplary embodiment is not
limited thereto. For example, as shown in FIG. 29 to FIG. 31, a
bulging portion 118, a claw portion 120 and a folded over portion
122 may be formed and employed as a projection portion at the rear
end portion of the bottom wall 30B of the lower rail body 30. As
shown in FIG. 32, configuration may also be made with an L-shaped
fitting 124 fixed to a rear end portion of the bottom wall 30B
employed as a projection portion. As shown in FIG. 33,
configuration may also be made with a screwed-in bolt 126 at the
rear end portion of the bottom wall 30B employed as a projection
portion. A bolt used for fastening the lower rail body 30 to the
bracket 34, can, for example be employed as the bolt 126, as shown
in FIG. 34.
[0154] As shown in FIG. 35, a projection portion 128 may be formed
by cutting around and projecting out a portion of the bracket 34.
In such cases, the projection portion 128 can also be employed for
length direction positioning of the lower rail body 30 when
assembling together the bracket 34 and the lower rail body 30.
Since the load input from the upper rail body 38 can directly
supported by the bracket 34 (on the vehicle body side), a high
rigidity can be secured and also the lower rail body 30 can be
prevented from breaking or deforming due to the load input to the
lower rail body 30. Furthermore, an increase in cost or weight can
be avoided due to the configuration utilizing previously present
components.
Third Exemplary Embodiment
[0155] FIG. 36 is a schematic diagram of a slide rail 132 that is a
configuration member of a vehicle seat 130 according to a third
exemplary embodiment of the present invention (see FIG. 38). FIG.
37A is a vertical cross-section corresponding to line L-L in FIG.
36, and FIG. 37B is a vertical cross-section corresponding to line
M-M in FIG. 36.
[0156] The slide rail 132 is configured basically the same as the
seat body 12 according to the second exemplary embodiment, however
the placements of a projection portion 114 and a projection portion
116 have been front-rear reversed.
[0157] In the vehicle seat 130 according to the present exemplary
embodiment, force due to inertia of a seated occupant during a
vehicle frontal impact is input to a belt anchor (not shown in the
drawings), resulting in an overload F4 input upwards in the vehicle
to the seat body 12, as shown in FIG. 38. When this occurs, an
overload F5 is input downwards to the front end portion side of the
upper rail 26. When the front end portion side of the upper rail
body 38 bows downwards due to the load F5, as shown in FIG. 39A,
the projection portion 116 provided to the front end portion of the
bottom wall 30B of the lower rail body 30 makes contact with the
bottom face of the upper rail body 38. Bowing of the front end
portion side of the upper rail body 38 is thereby suppressed.
[0158] When this occurs, an overload F6 is input upwards to the
rear end portion side of the upper rail 26, as shown in FIG. 38.
When the rear end portion side of the upper rail body 38 bows
upwards due to the load F6, the projection portion 114 provided at
the rear end portion of the top wall 30A of the lower rail body 30
makes contact with the top face of the upper rail body 38. Bowing
of the rear end portion side of the upper rail body 38 is
accordingly suppressed.
[0159] The vehicle seat 130 according to the second exemplary
embodiment is accordingly capable of suppressing the upper rail 26
from bowing during a frontal impact, and supporting rigidity
(strength requirements) of the seat body 12 during a frontal impact
can accordingly be secured. Similarly to the slide rail 22
according to the first exemplary embodiment, the supporting
rigidity to the seat body 12 in normal operation is lowered by
making the separation between the front and rear pair of slide
guides 42, 44 narrower.
[0160] In the second exemplary embodiment and the third exemplary
embodiment, configuration is made such that the projection portion
116 is fixed to the top face of the bottom wall 30B of the lower
rail body 30, however there is no limitation thereto. Configuration
may be made, as shown in FIG. 40, with the projection portion 116
fixed to the bottom face of the upper rail body 38.
[0161] The upper rail body 38 is formed with a substantially
W-shaped cross-section, with the seat left-right direction end
sides of the bottom face of the upper rail body 38 disposed closer
to the bottom wall 30B of the lower rail body 30 than a seat
left-right direction central portion of the bottom face of the
upper rail body 38. Accordingly, as shown in FIG. 41, configuration
may be made with a projection portion 134 provided between a seat
left-right direction end side of the bottom face of the upper rail
body 38 and the bottom wall 30B of the lower rail body 30. In such
cases the projection portion can be made more compact and lighter
in weight since the height dimension of the projection portion can
be lowered.
Fourth Exemplary Embodiment
[0162] FIG. 42 is a schematic diagram of a configuration of a
vehicle seat 136 according to a fourth exemplary embodiment of the
present invention. FIG. 43 is a schematic diagram illustrating a
portion of a slide rail 137 of the vehicle seat 136. In the vehicle
seat 136 the seat body 12 is equipped with a lifter for adjusting
the seating plane height of the seat cushion 14, and a seat cushion
frame 18 is coupled to a upper rail 26 through a front side link
member 138 and a rear side link member 140. A block shaped
projection portion 144 is provided below a coupling section 142 of
the rear side link member 140 and the upper rail 26 (coupling
section of the seat body 12 and the upper rail 26). The projection
portion 144 is fixed by welding to the bottom face of the upper
rail body 38, so as to face a bottom wall 30B (not shown in FIG.
43) of the lower rail body 30 with a specific gap separation
thereto.
[0163] In the present exemplary embodiment, when the rear end side
of the upper rail body 38 bows downwards, bowing of the upper rail
body 38 is suppressed by the projection portion 144 making contact
with the bottom wall 30B of the lower rail body 30.
[0164] FIG. 44 is a graph illustrating a comparison of load against
bowing characteristics for a case when the projection portion 144
is provided below the coupling section 142 (the present exemplary
embodiment) and when the projection portion 116 is provided to the
rear end portion of the lower rail body 30 as in the second
exemplary embodiment. It can be seen from FIG. 44 that when the
projection portion 116 is provided, bowing of the upper rail body
38 can be suppressed at an earlier stage to when the projection
portion 144 is provided (see X3 and X4 in FIG. 44). However, when
the projection portion 144 is provided the rise in load from
suppressing bowing of the upper rail body 38 rises more rapidly
than when the projection portion 116 is provided, resulting in high
rigidity.
[0165] Namely, in the present exemplary embodiment, when the
projection portion 144 is provided below the coupling section 142
(or the vicinity of below), since the coupling section 142 can be
given direct support to the seat body 12 without being influenced
by deformation of the upper rail body 38, excellent supporting
rigidity to the seat body 12 is achieved.
Fifth Exemplary Embodiment
[0166] FIG. 45 is a schematic diagram illustrating a configuration
of relevant portions of a vehicle seat 146 according to a fifth
exemplary embodiment of the present invention. FIG. 46A is a
vertical cross-section corresponding to line N-N of FIG. 45. FIG.
46B is a vertical cross-section corresponding to line O-O of FIG.
45. FIG. 46C is a vertical cross-section corresponding to line P-P
of FIG. 45. FIG. 46D is a vertical cross-section corresponding to
line Q-Q of FIG. 45.
[0167] In a slide rail 148 of the vehicle seat 146, as shown in
FIG. 46A, a left and right pair of projection portions 150 are
fixed to the bottom face of the front end portion of the top wall
30A of the lower rail body 30. As shown in FIG. 46B, a left and
right pair of projection portions 152 are provided to the top face
of the front end portion of the upper rail body 38. Furthermore, a
projection portion 154 is fixed to the bottom face of the rear end
portion of the upper rail body 38, and as shown in FIG. 46D, a
projection portion 156 is fixed to the top face of the rear end
portion of the bottom wall 30B of the upper rail body 38.
[0168] In the present exemplary embodiment, when a vehicle has been
involved in a collision from behind in a state in which the upper
rail 26 is slid towards the seat rear side with respect to the
lower rail 28, as shown by the solid lines in FIG. 45, bowing of
the upper rail body 38 is suppressed by the projection portions 152
making contact with the top wall 30A of the lower rail body 30 and
the projection portion 156 making contact with the bottom face of
the upper rail body 38.
[0169] As shown by the double-dot intermittent lines of FIG. 45,
when a vehicle has been involved in a collision from behind in a
state in which the upper rail 26 is slid towards the seat front
side with respect to the lower rail 28, bowing of the upper rail
body 38 is suppressed by the projection portions 150 making contact
with the top face of the upper rail body 38 and the projection
portion 156 making contact with the bottom face of the lower rail
body 30.
[0170] In this manner, in the present exemplary embodiment, bowing
of the upper rail body 38 can be suppressed from occurring during a
collision from behind irrespective of the sliding state of the
upper rail 26.
[0171] In a case in which the front and rear placements of the
upper rail 26 and the lower rail 28 are reversed, bowing of the
upper rail body 38 can be suppressed from occurring during a
frontal collision irrespective of the sliding state of the upper
rail 26.
[0172] In the second exemplary embodiment to the fifth exemplary
embodiment, the front lower projection portion 50, the rear lower
projection portion 60, the front upper projection portion 52 and
the rear upper projection portion 58 according to the first
exemplary embodiment have been omitted in the illustrations for
ease of explanation. However the invention as implemented by the
first exemplary embodiment and the invention as implemented by the
second to the fifth exemplary embodiments can both be applied to
the same vehicle seat at the same time. For example, it is possible
to employ the projection portion 116 illustrated in FIG. 22 or FIG.
36 in common with (as the same component) the front lower
projection portion 50 or the rear lower projection portion 60
illustrated in FIG. 2, or it is possible to employ separate members
therefore by implementing slight changes to the profile and/or
slight changes to the placement.
* * * * *